Operational research refers to the use of theories and methods of mathematics, statistics, computer science, engineering and other disciplines to study complex management and decision-making problems, so as to optimize resource allocation, improve production efficiency, and improve economic benefits and enterprise performance.

1. Linear programming model.

Linear programming model is a decision analysis tool based on linear mathematical method, which can be used to solve the optimal decision-making problems such as optimizing production plan, transportation scheduling and resource allocation. Among them, the objective function and constraint conditions are linear, and mathematical foundations such as optimization theory and linear algebra are used in the solution process.

2. Integer programming model.

Integer programming model is an analysis method based on integer programming technology. When solving the problems of production logistics, engineering optimization and economic decision-making, it not only meets the basic limitations of linear programming model, but also requires the decision variables to take integer values. Integer programming model is suitable for applications that need to discretize problems, such as manufacturing production scheduling and investment decision-making.

3. Nonlinear programming model.

Nonlinear programming model is a decision analysis tool involving nonlinear objective function and nonlinear constraints, which is mainly used to maximize or minimize the function value under resource constraints, such as maximizing output and minimizing cost.

4. Queuing system

Queuing system refers to the application of queuing theory to process analysis and production scheduling under the condition of insufficient personnel, equipment or resources. It studies the impact of unexpected events on handling services, the time to deal with problems, etc., and can be applied to customer service, transportation and production.

5. Supply chain management.

Supply chain management is all or part of the management of product flow, information flow and capital flow. It aims at optimizing supply chain cost, shortening supply chain cycle and improving supply chain service level, and uses many operational research tools, which are mainly used in manufacturing, retail and service industries.

6. Waiting line rule (isochronous curve)

Waiting line refers to the average output speed curve under different waiting time in process, service or production, and is an important graph for making scheduling strategy and improving production plan.